Ligator

ABSTRACT

An apparatus applicable for the ligation of internal tissue in a created or natural cavity in animals or in the human body, for example varicose veins in the gullet or a duodenal diverticulum, by means of an elastic band ( 19 ) while observing the ligations through an endoscope. The apparatus includes an automatic trigger unit ( 1 ) mounted firmly on the handle of the endoscope which can release a number of elastic bands ( 19 ) with the aid of a single-stranded trigger cord ( 11 ). Only a single elastic band ( 19 ) is released for each ligation thereby establishing a one-man-operated apparatus.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of copending U.S. utility applicationentitled, “Ligator,” having Ser. No. 11/919,775, filed Nov. 1, 2007, nowU.S. Pat. No. 8,845,516, which is a §371 national stage application ofPCT International patent application Ser. No. PCT/DK2005/000312, filedMay 9, 2005, both of which are entirely incorporated herein byreference.

This invention relates to medical ligating instruments, and moreparticularly to devices used to ligate body tissue in a created ornatural cavity in animals or in the human body, for example varicoseveins in the gullet or a duodenal diverticulum, by means of individualelastic bands while observing the ligations through an endoscope.

It takes supreme effort to maneuver an endoscope while you ligateinternal tissue in a created or natural cavity in animals or in thehuman body, for example varicose veins in the gullet or a duodenaldiverticulum, by means of individual elastic bands while observing theligations through an endoscope if the surgeon is supposed to maneuverthe endoscope and activate the release of a number of elastic bands allby himself. Therefore it is common practice for an assistant to help thesurgeon while he maneuvers the endoscope and releases elastic bandsduring the actual ligation.

Furthermore, it is very inconvenient for the patient when the endoscopeis lead into the gullet or other openings of the human body. Thereforeit most advantageous to perform a safe and quick operation.

For known ligating instruments related to the present invention, thetrigger unit is not firmly fixed at the distal end the endoscope, seefor example U.S. Pat. No. 6,149,659. Therefore you must hold the triggerunit firmly with one hand, and with the other hand you can draw thetrigger cord to obtain the ligation of the desired varix ordiverticulum. A third and eventually a fourth hand are needed to holdand maneuver the endoscope.

For known ligating instruments related to the present invention, two ormore trigger cords are used in releasing the rubber bands, see, forexample U.S. Pat. No. 6,235,040 and WO 9716120. The consequence ofhaving two or more trigger cords is that the cords can cross one anotherand squeeze, for example a varix, which easily can result in bleedingand put the patient's health at risk and make the treatment verytroublesome.

Therefore it is an object of the present invention to provide animproved ligating instrument where the surgeon can very quickly and withgreat safety perform the operation by himself using an automatic triggerunit according to the invention, which further can lead to reduction ofstaff in connection with the surgery.

Further it is an object of the present invention to provide an improvedligating instrument where the great risk of squeezing body tissue, forexample a varix in the gullet, is eliminated in connection with theligation.

The first mentioned object according to the present invention can beachieved using a ligating instrument, which includes a trigger unitmounted firmly on the endoscope. Hereby is produced a one-man-operatedendoscope, where the surgeon has complete control over the endoscope.

A grip of the trigger unit on the endoscope at a joint between the tubeand the handle of the endoscope can be secured by means of a U-shapedbracket on a connecting part.

To enable gripping of the trigger unit on the endoscope at the jointbetween the tube and the handle of the endoscope no matter the diameterof the endoscope, the connecting part can be provided with a fixture,for example VELCRO™ tape.

When the U-shaped bracket is connected with the trigger unit by means ofone or more toggle joints, one can secure a socket-shaped nozzle to theproximal end of the accessory channel of the endoscope and afterwardsturn the U-shaped bracket to fasten the bracket between the tube and thehandle of the endoscope.

It has surprisingly been revealed that it is possible to overcome thedrawbacks that occur when trigger cords cross one another, which canlead to squeezing of internal tissue, such as a varix, that consequentlycan lead to severe bleeding, when you have a single-stranded triggercord at the distal end of the trigger cord.

The use of a single-stranded trigger cord implies an adequate large sizeof the knots or beads because a single knot or bead on the distal end ofthe trigger cord is responsible for guiding an elastic band over thedistal end of a bush and releasing it for the ligation of specificinternal tissue.

When the trigger cord is manufactured of metal wire, preferably twistedmetal wire, at least two essential advantages are achieved becausetwisted metal wire is simultaneously rigid and very flexible. Thereforethe surgeon has an optimal touch with the firing of elastic bands.Because of the high strength of metal wires, a very tiny dimension canbe used which leaves the optimal space in the accessory channel forflushing if bleeding occurs during the ligation.

The use of the one-man-operated, automatic, dual-fixed, trigger unitaccording to the invention provides an adapted up-winding of the triggercord corresponding to the release of a single elastic band at the distalend of the endoscope. The up-winding can be achieved by simultaneouslyturning the revolving parts to the built-in stop at their extremeposition where the release of an elastic band takes place, and thesimultaneous compressing of a built-in spring is performed. After therelease of an elastic band has taken place, the revolving part at whichthe proximal end of the trigger cord is attached leaves its engagementwith the part that has the winding track and automatically returns toits starting point while the trigger cord is coiled up on the windingtrack.

When the trigger unit has sounded a signal at the extreme position ofthe revolving parts, the surgeon instantly becomes aware that therelease of an elastic band has taken place, after which the surgeoninstantly can let go of the revolving parts, after which the tensedrevolving part automatically returns to its starting point. Hereby isobtained the obvious advantage that the operation can be performed in ashorter amount of time, which means less discomfort for the patient.

For flushing if bleeding occurs during the ligation, the trigger unitaccording to the invention has an integrated canal upon which a flexibleinjection tube can be mounted to the ligator. When the injection tube ismounted, the surgeon can flush the fiber optic from any angle at theproximal end of the endoscope by the means of a syringe.

By manufacturing a bush according to the invention, there is provided aretainer for the elastic bands by the use of a single-stranded triggercord. The use of a single-stranded trigger cord leads to a more safeoperation for the patient. Moreover, the bush loaded with the elasticbands is considerably easier and therefore less expensive to produce.

The bush loaded with elastic bands is prepared to be connected with thedistal end of an endoscope after joining the trigger cord from the bushwith the trigger cord from the trigger unit via the accessory channel ofthe endoscope.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a trigger unit.

FIG. 2 is a perspective view of a trigger unit where a trigger cord isguided into the trigger unit.

FIG. 3 is a longitudinal section through a bush upon which is placed aflexible trigger cord having beads and elastic bands.

FIG. 4 is a perspective view of a trigger unit according to the presentinvention shown firmly mounted on the proximal end of an endoscope.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates a trigger unit, which is generally identified withthe reference number 1. The trigger unit 1 has a connecting part 2 onwhich a socket-shaped nozzle 3 is mounted. Further, a U-shaped bracket 4is mounted on the connecting part 2 by means of a toggle joint 5. Tworevolving parts 6 and 7 of the trigger unit 1 can revolve together on ashaft, not shown, since the shaft is lead through a bedding, not shown,in the connecting part 2. The first revolving part 6 has a winding track8 which is meant for the guiding and winding of a trigger cord 11. Theother revolving part 7 has a built-in spring, not shown, which after therelease of an elastic band 19 ensures that the revolving part 7 leavesits engagement with the revolving part 6 and automatically returns toits starting point, while the revolving part 6 ensures automatic windingof the trigger cord 11 on the winding track 8. From the socket-shapednozzle 3, the trigger cord 11 is lead through a hole 9 in the windingtrack 8 and into revolving part 6 and revolving part 7, and further to acord clamp 10 where the cord is secured. The cord clamp 10 is shown inits locked position in FIG. 1.

FIG. 2 illustrates the trigger unit 1 as seen from below, where theU-shaped bracket 4 is connected with the trigger unit 1 by means of oneor more toggle joints 5.

FIG. 3 illustrates how the distal end of the trigger cord 11 is providedwith a number of beads 17. The trigger cord 11 is, as shown, guidedthrough a bush 18 and folded backwards on the outer end of the bush. Thebush 18 is mounted on the distal end of the tube 14 of the endoscope.Elastic bands 19 are placed on the bush 18 so that they encircle thebush with the trigger cord 11 in between the beads 17.

If the trigger cord 11 is pulled inwards into the tube of the endoscope4, meaning downwards in FIG. 3, the beads 17 on the distal end of thetrigger cord 11 will guide the elastic bands 19 over the distal end ofthe bush 18 and successively release the elastic bands 19.

Pulling of the trigger cord 11 into the tube of the endoscope 4 isachieved when the proximal end of the trigger cord 11 is fastened on thetrigger unit 1 by means of the cord clamp 10. The revolving parts 6 and7 revolve from the starting position to their extreme position wherethere is a built-in stop, during which the release of an elastic band 19takes place.

FIG. 4 illustrates the trigger unit 1 mounted on the handle 13 of anendoscope. The trigger cord 11 is guided from the proximal opening 15 ofthe endoscope to the trigger unit 1, on which a flexible injection tube12 can be fixed. The dual-fixed trigger unit 1 is partly fixed byanchoring the socket-shaped nozzle 3 of the trigger unit 1 into theaccessory channel 15 of the endoscope and partly by the connecting unit2 of the trigger unit 1 via the U-shaped bracket 4.

In operation, the distal end of the endoscope is supplied with a loadedbush 18 and is guided over a varicose vein while the vein is observedthrough the endoscope or on a monitor. If it is necessary, the varicosevein can be sucked into the bush 18 using a pump.

When the varicose vein is in place, as can be observed through theendoscope or on a monitor, an elastic band 19 can be released. The band19 then places itself around the varicose vein, which leads to halt ofblood circulation and consequently to necrosis of the tissue. When thedistal end of the endoscope is provided with a loaded bush 18, one ormore varicose veins can be treated in the same manner as long as thereis an elastic band 19 on the bush 18. In this way, individual elasticbands 19 can be placed around separate varicose veins.

The invention claimed is:
 1. A ligator for use with an endoscope havinga tube and an accessory channel, the ligator comprising: a trigger unitincluding a revolving part, a built-in spring that applies an opposingspring force to the revolving part when it is turned, and a built-instop that limits turning of the revolving part to an extreme positionbeyond which it can no longer be turned; a nozzle adapted to be receivedwithin the accessory channel of the endoscope; a bush adapted to mountto an end of the tube of the endoscope, the bush supporting elasticbands to be deployed for ligation; and a trigger cord connected at afirst end to the trigger unit and connected at a second end to the bush;wherein the revolving part is adapted to cause deployment of an elasticband when the revolving part is turned from a starting position to thebuilt-in stop at the extreme position, and to automatically return tothe starting position under the force of the built-in spring after beingreleased, at which point it is ready to be turned again to deploy thenext elastic band.
 2. The ligator of claim 1, wherein the revolving partincludes a cord clamp that secures the first end of the trigger cord tothe trigger unit.
 3. The ligator of claim 1, wherein the trigger unitincludes a further, separate revolving part.
 4. The ligator of claim 3,wherein both revolving parts can be turned in a forward direction fromthe starting position toward the extreme position, but the further,separate revolving part cannot return to the starting position after ithas been rotated to the extreme position.
 5. The ligator of claim 4,wherein the further, separate revolving part includes a winding trackupon which the trigger cord is guided and wound.
 6. The ligator of claim5, wherein the winding track is aligned with the nozzle.
 7. The ligatorof claim 5, wherein a hole is provided within the winding track throughwhich the trigger cord passes.
 8. The ligator of claim 1, wherein thetrigger unit is further adapted to sound a signal at the extremeposition to signal to a user that release of the elastic band hasoccurred.
 9. A method for deploying an elastic band using a ligatorhaving a nozzle received within an accessory channel of an endoscope,the method comprising: turning a revolving part of the ligator away froma starting point against the force of a spring so as to pull a triggercord of the ligator that is connected to a bush that is mounted to anend of a tube of the endoscope, the bush supporting elastic bands thatcan be deployed for ligation; continuing to turn the revolving partuntil it reaches a built-in stop of the ligator located at an extremeposition beyond which the revolving part can no longer be turned so asto cause an elastic band to be deployed from the bush; and enabling therevolving part to automatically return to the starting point under theforce of the spring, at which point the revolving part is ready to beturned again to deploy the next elastic band.
 10. The method of claim 9,wherein enabling the revolving part to automatically return comprisesreleasing the revolving part.
 11. The method of claim 9, furthercomprising winding up the trigger cord on a further, separate revolvingpart that cannot return to the starting point once the extreme positionhas been reached.
 12. The method of claim 9, wherein the ligator soundsa signal at the extreme position to signal to a user that release of theelastic band has occurred.